Vacuum tube



E.' G. MURPHY sept. 3o, 1930.

vAcuuu TUBE Eiled Ngv. 28, 1927 fifa/*4% l.

Patented Sept. 30,' 1930 narran EDMUND GUYER MURHY, OF CHECAGO, ECLLINOIS vacuum; TUBE Application fried November 28,4192?. Serial No. 236,260.

' My present invention, which is an improvement over that disclosed 1n my Patent No.

15, 1929, for improvements in `vacuum 5 tubes, relates to improvements in wireless receiving and transmitting apparatus, and more particularly toA vacuuln or electron tubes of the type suitable for receiving` and transmitting" electrical oscillations.

The object of the invention is to provide an apparatus of the kind described that will be more efficient in receiving and transmitting electrical oscillations.

- Another ob] ect-is to provide a vacuum tube 15. wherein is incorporated' a novel combination ofindividually*selective amplifying` and detecting. elements. f Y

A further object of .theinvention is to provide means in a vacuum tube augmenting in practically two-foldY ratio its receiving@andr y transmitting powers without ythe necessity of additional apparatus.

Other objects and advantages ofthe method and construction employedv will. ap-

pear more fully in the .hereinafter specification when taken in connection with the accompanying drawings .in which, v

Fig. 1 isa side elevation of a vacuum tube embodying my invention..

Fig. 2 is a vertical section taken on line V2--2 of Fig. 1. f

' Fig. 3 is anenlarged of the novelinsertible thermionic valve Fig. 4 isl a longitudinal section of the glass 35 envelope of the thermionic valve E beforey the insertion. ofthe electrodes therein and the sealing `ofthe envelope by the fusing of the glass cap therein. y 1

Figi is a. perspective view of the anode electrode used in the insertible thermionic valve Fig. 6 isa verticalsection of my. devicewith the'insertible valve Bin operati-ve po- .15 sition, the cathodes of tube A and valve B being connected in parallel r; partsof tube' A being broken away, while valve Bfis illustrated inielevation. v y

. Fig. 7 is a view similar to Fig.` 5,' showing 5o all of the electrodes of tube LA. and 'valve B longitudinal sectiony connected in parallel, the transformer being fremoved from valve-B. 1,699,011. for vacuum tubes, dated January tube, comprising the cathode 13, cathode supporting rod'lB-Qgrid 14, grid lead 14', anode ,15 andthe resilient contact 16 connected to grid lead 14. 17 designates the base of the tube A having the orifices 18 wherein are crnnpedorotherw1se suitably secured the metal tubular sections 19 and 20 accommodating the insertible. three electrode thermionic-valve B on which is Wound the transformer 'C ,forming a part thereof. In the base of the tube A are also secured the eX- 4terior cathode prongs 21, 22 and the grid `and anode prongs 23 and 24, respectively.

The envelope of the novel thermionic valve and transformer combined B-O, comprises Ya glass tube 25 anda cap 25 therefor, having reentrant, axially positioned, tubular projections 26 with flares 27 27 and stems 28 28', the latter being adapted to providea seat forone end of a control grid 29 ,which has a connection 30 to an outside collar 31v seated in jone of the circumferential grooves 32, the` under side of which form bulges 83 on'the inside wall of the envelope to 'serve as anchorages against longitudinal "slippage of the tubular anode 34,.-the anode. A34 being formed 'of a sheet o f aluminum, nickel, 'copper AVo r other `suitable metal,

wrapped into a roll and then permitted to l expandagainstfthe sides ofthe glassenvelope 25 .behind the circumferential bulges BSf-the 'tongue 34f of the anode being .protruded through one of theapertures 35 in the bulges 83 and soldered or otherwise suitably secured to the collarB which is' connected to the pri- 1nary37 of the transformer C.

rllhrough"thev axial openings 36( 3.6 inthe tubular reentrant projections `26 26 of the envelope 25and' cap 25 is'str'etched the cathode B8, the ends 'offwhich are secured in the glass envelope Y andv cap by fusing of the glass,the cap 25 being fused to the inner side of the envelope after the insertion of the electrodes therein by a method hereinafter described in detail. Metal caps 39 and 40, soldered to the ends of the cathode 38, are cemented to the sealed glass envelope 25 and the cap 25', completing the tube B shown in Fig. 3.

Upon the insertion of tube A into a conventional tube socket with suitable sources of lathoC-e, grid and anode electrical energy connected thereto, the cathode circuits Will be. completed through prong 22, Wire 41, metal tube section 13, metal cap 40 of tube B, through cathode 38, metal cap 39, metal tube section 19, cathode supporting rod 13', cathode 13 of tube A to prong 21V-the cathodes of tube A and thermionic valve B, in this instance, being energized in series.

Electrical oscillations may be superimposed on the grid 29 of valve B via the prong 23, resilient Contact 23, metal collar 31 and inside connecting lead to grid 29. Potential for the anode 34 of tube B, as illustrated in F ig. 2, is impressed through prong 24, resilient contact 24 which may be of comparan tively high resistance in order to obtain a drop of potential thereacross for a purpose that will hereinafter appear, through primary 37 of transformer C, to anode 34.

The output of valve B, which in Fig. 2, is a soft or gas filled tube, and in Fig. 6, is a tube of highpvacuum, is impressed on the high vacuum amplifying tube in the usual manner employed in cascade amplification. The secondary 37 of transformer C receives the output current of thermionic valve B by inductive coupling from the primary 37, the resilient Contact prong 16 of tube A conveying the current. via grid lead 14 to grid 14,- an amplified thermionic current flowing in the circuit of the anode 15 of tube A. The grid return for tube A is made through contact 23" which is integral with prong 23, the latter prong beingpreferably of higher resistance than Contact 23 for the purpose of securing a drop of potential thereacross.

Inductive feedback or regeneration in tube B is obtained by means of the transformer C, the stronger oscillations in the circuit of the anode 34 being inductively reimpressed on the secondary 37 of the transformer C connected to grid 29 via contacts 23, 23, collar 31 and connection 30,*-thereby reinforcing the original grid potential, the reinforced grid. oscillations being recoupled to the anode,-the cycles repeating until a maximumranode current is built up in an inappreciable space of time, in the manner Well known. By sliding valve B transversely. the degree of regeneration may be varied as the valve B is slid to agreater or less extent. By an inspection of the electrodes of tube A and the circuits connected therewith. it Will be seen that regeneration in tube A occurs simultaneously with that secured in the valve B,- the primary 37 of transformer C being connected to anode 34 of valve B and to anode 15 of tube A, While secondary37 is connected to grid 29 of valve B and to grid 14 of tube A,-the process of circuit regeneration then taking place in tube A simultaneously and in a manner similar to that described with reference to valve B. The potentials impressed on grids 14 and 29 of tube A and valve B respectively, it Will be observed, are made variable by the sliding of valve B transversely.

The collar 31 on valve B, which here, for the purpose of illustration, is shown of comparatively small Width, is preferably in practice made slightly wider With a view to permitting the resilient contact 23 to engage same slidingly when the valve B is thrust transversely, carrying the primary 37 and the secondary 37 over the prongs 24 and 23.

The anode 15 of tube A, as shown in Fig. 2, is connected to the same source of potential as anode 34 of valve B, but in the particular form illustrated, is preferably, for the purpose of amplification, impressed with a higher potential than the anode of valve B, this result being readily obtained by the use of a high resistance in the resilient contact 24. By this means, I obtain a drop of potential across the contact 24, this being desirable when tube A is used as the amplifying tube. Jhen the tube A is of the gas filled type fer use as a detector, the lead 41, on the contrary, may be of sufiicient resistance to cause a drop of potential thereacross with respect to anode 15,-the anode 34 of valve B in this instance receiving a higher impressed voltage under circumstances deemed desirable.

1n Fig. 6, the mode of energizing the separate cathodes of tube A and valve B in parallel, is shown. Herein the cathode prong 21 is merely Wired to metal tube section 19 via the lead 21, While the cathode'prong 22 is connected to opposite metal tube section 18, all other connections being identical With those shown in Fig. 2. The method employed in my device as shown in Fig. 6 is generally preferable to that disclosed in Fig. 2, since in the former, the cathodes being Wired in parallel, there will be no necessity of reducing the voltage across the cathode of tube A should it be desired to Withdrav7 the thermionic valve B. The drop of potential that occurs when the cathodes of vacuum tubes are Wired in series, however, offers Well known advantages where it is desired to supply electrical energy at a. comparatively high voltage and small amperage. lVith the slight change in the Wiring indicated, either method may be employed for operating the cathodes in series or parallel.

In the process of manufacture of the thermionic valve B, the grid 29 is first inserted in the envelope 25 and connection 30 passed through slot in the bulge 33; the anode luf) liu

is next inserted in the envelope in the form of a roll and allowed to expand against the sides of the tube 25 in the manner illustrated in Fig. 3, the tongue 34 of the anode beingprctruded through the other slot 35,-the cathode 38 is now passed through the reentrant projections 26 and 26 of the tube and cap respectively, the latter now being applied. The opening 36 and the slots 35 arefused, the glass cap 25 inserted in the envelope 25 and fused thereto.V The envelope 34 is now evacuated through Vopening 36 which is immediately sealed by fusing upon the completion of the evacuation. The collar 31 is then applied and soldered to the lead wire 30, the tongue 34 to prima-ry 37, the ends of the cathode 38 soldered to the two metal caps 39, 40 which are now permanently affixed to the glass envelope b-y cementing. This' completes the manufacture of valve B.

The dual thermionic valve herein described and illustrated is exceedingly flexible in adapting itself toa wide variety of uses such as; a combined detector and audio frequency Y ,oscillation amplifier, a combination radio frequency oscillation amplifier and a detector of oscillations, a'combination twotube radio or audio frequency oscillation amplifier. It is also within the province of my invention to connect all the electrodes of tube A and valve B in parallel by merely removing the transformer C and placing contact 24 on 'collar 36 and the resilient contact 16 on collar 31. The use of vacuum tubes wired in parallel to handle a heavy current output in the last audio stage of multiple tube receiving sets, and particularly in commercial radio transmitting apparatus where it is desirable to radiate a comparatively heavy amperage from the antenna circuit, presents marked advantages over the wiring of tubes in series. My novel combination tube and thermionic valve when wired in parallel, by its economy of space and interchangability is particularly adapted to this method of wiring.

The transformer C wound on the exterior of the thermionic valve B, it is also to be noted, by electro-magnetic induction, exerts a well known modifying effect on the .electronic stream from the cathode andon the currents in the circuits ofthe grid and anode of the thermionic valve.

While I have herein described and in the accompanying drawings illustrated a preferred embodiment of my invention, I do not thereby desire nor intend to limit myself specifically thereto as it will be understood that the device is susceptible of the widest variation and modification within the scope of the invention as defined in the appended claims.

What I claim as new and desire to secure by Letters Patent is: l

l. An electro-responsive device comprisin g, in combination, a plurality of thermionic valves, one of said thermionic valves being -be obtained.

electrically connected to Vthe second of said ther-mionicvalves-and inclosed in means mechanically fastened to the exterior of said second valve.

` 2. An electro-responsive device comprising a vacuum tube having a` plurality of electrodes, and thermionic means removably insertible within the base` of said vacuum tube whereby said plurality of electrodesmay be energized thro-ugh said means. i i if 3. A vacuum tubehaving a plurality v-of electrodes, andmeans including a themionic member within the basezofsaid vacuum tube whereby a variable potential may be impressed, upon at least one of saidplurality of electrodes. l V a' y 4. An electro-responsive deviceY comprising a vacuum tube, and means mechanically and electrically connected to said vacuum tube and a thermionic valve, removably andv adjustably mounted in Saidmeans to serve as a medium through which said vacuum tube may be energized.V v

5. A Vvacuum tube having` a plurality `onf electrodes, and thermi'onic means removably insertible within the base of saidvacuum tube and means-whereby said plurality of electrodes may be impressedwiththe output of said thermionic means y i 6. A vacuum tube comprising,,incombination, an envelope containinga plurality of electrodes, abase secured to said envelope, avthermionic valve kwithin said base operatively connected -to-.said electrodes, means whereby said electrodes and said thermionic valve may be simultaneously lenergized and deenergized, andmeans whereby the current output of said thermionic ,valve may be impressed on said electrodes. Y l I 7, In combination, a plurality of individual vacuum tubes of dissimilar type operatively. connected togcther, a socket in the base lof one of said tubes, the other ofsaid vacuum tubesbeing removably embodied within said socket. f Y. i i Y 8. An electro-responsive `device comprising, in combination, an amplifying vacuum tube, means within the base of said amplifying vacuum tube to operatively receive therein a gaseous thermionic valve, and means whereby the electricaloutput of said gaseous thermionic valve can be impressed on said vacuumtube.

V9., An electro-responsive device comprising, in combination, a vacuum tube and removable means within the base of4 said vacuum tube whereby circuit regeneration may l0. An oscillation responsive device comprising, in combination, a vacuum tube including cathode, anode and grid electrodes, and adjustable electro-inagneticmeans within the base ofsaid tube whereby electrical oscil- .lationsimpressed 'on the anode circuit from the gridcircuit of said vacuum tube may be reimpressed on said grid circuit and thence back again on said anode in cycles, whereby circuit regeneration in said vacuum tube is secured.

11. An electro-responsive device comprising, in combination, a vacuum tube having cathode, anode and grid electrodes, a thermionic valve within the base of said vacuum tube, said thermionic valve having cathode, anode and grid electrodes, means to impress the potential of the therniionic valve on the vacuum tube, and additional means within the base of the vacuum tube whereby circuit regeneration of both the vacuum tube and the thermionic valve is simultaneously obtained.

12. An electro-responsive device comprising, in combination, a vacuum tube having a plurality of electrodes, a thermionic valve within the base of said vacuum tube, means to impress the potential of said thermionic valve on the electrodes of said vacuum tube, and means whereby the current output of said vacuum tube and said thermionic valve are combined together within the base ofsaid vacuum tube.

13. An electro-responsive device comprising, in combination, a vacuum tube having a plurality of electrodes, a thermionic valve within the base of said vacuum tube, said thermionic valve having a plurality of electrodes, additional means within the base of said vacuum tube whereby the said electrodes of both the vacuum tube and the thermionic valve may be simultaneously energized and deenergized, means whereby the output potential of said thermionic valve may be impressed on said vacuum tube, and means whereby the combined electrical output of both the vacuum tube and the thermionic valve may be obtained from a contact element on the exterior of said vacuum tube.

14. An electro-responsive device comprising, in combination, a plurality of thermionic valves, each of said valves having cathode, anode and grid electrodes, one of said valves being operatively housed within the base of and operatively connected to the other of said thermionic valves, and means mounted on Vone of said thermionic valves whereby oscillation regeneration in the circuits of the electrodes of both of said thermionic valves is simultaneously' obtained.

15. An electro-responsive device comprising, in combination, a plurality of thermionic valves, one of said t-hermionic valves being wound with an inductance and being removably insertible within the base of the other of said thermionio valves, and means whereby circuit regeneration in the electrodes within each of said thermionic valves and the circuits connected therewith is simultaneously obtainedV by means of said inductance.

16. A thermionic valve comprising atubular envelope, cathode, grid and anode electrodes individually supported within said envelope, said anode electrode consisting of a sheet of metal rolled into a resilient roll and then permitted to expand against the interior circumference of said envelope, and a transformer wound on the exterior of said envelope and having connections to the grid and anode electrodes therein, whereby regeneration in the circuits connected to said grid and anode electrodes may be obtained.

17. A thermionic valve in the form of a cartridge, said thermionic valve being removably and adjustably insertible within the base of a vacuum tube, means whereby said vacuum tube may be energized and deenergizcd through said thermionic valve, means whereby potentials of unequal strength may be simultaneously impressed on the grid and anode electrodes of both the thermionic valve and the vacuum tube and means whereby regeneration in the circuits connected with the said grid and anode electrodes is obtained.

18. An electro-responsive device comprising, in combination, a vacuum tube, a thermionic valve within the interior of means fastened te said vacuum tube and operatively wired in parallel therewith, and other means connected to the exterior of said vacuum tube whereby said vacuum tube and said thermionic valve may be simultaneously energized and deenergized.

In testimony whereof I have signed my name to this specification.

EDMUND GUYER' MURPHY. 

